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Permutation is the rearranging in a orderly fashion objects or values. Mathematically it defines an operation which arranges a number of objects i.e. digits in a specific order.

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Depending on the number of distinct objects the number of permutation group elements vary. For Example, For the 3 distinct objects we can generate 6 group elements and for 4 distinct objects we can generate 24 group elements Number of group elements= N! Where the ! Means N factorial, i.e., N! = 1x2x3x4x….x N